Fuel nozzle

[richardm]

Here' s a picture of a test i've conducted last week. Diesel fuel sprayed from a PT-6  engine fuel nozzle at about 180 psi.


Those nozzle are quite small, about 3/8 " and seem to be made of stainless  Quick search shows they made by Delavan.

Must be quite expensive when new ( anything aviation is )  but can probably be found on E Bay or other markets.

According to the PT-6 engine manual fuel pressure varies from 150 to 8oo psi during operation. Fuel flow at max power is around 500 pounds an hour and the engine has 14 of those nozzle. so one can do the math and get a good idea about what he can get from a number of nozzles

[racket]

Nice wide angle as well :-)

On my bike build I used pressures up to ~750 psi, the atomisation gets nice and fine at those sorta pressures with speedy combustion , all we need is a small hydraulic gear pump and an electric motor to drive it .

Having tried both spray nozzles and evap tubes , I think I'd opt for the high pressure spray especially as there are 12V motors and PWM controls available these days to make an easily controllable throttle arrangement rather than the more complicated mechanical one I made 25 years ago , it was a pain to get sorted .

Another benefit of high pressures is they are sorta self limiting with regards flow , the pressure required increases much faster than the fuel flow rate .

[richardm]

I tried a small hydraulic pump but diesel fuel promptly ruined the internal seals In a matter of minutes the pump was jammed.
This test was done with an homemade pump based on an old gerotor gear set I had

[richardm]

Also I once tried an automotive fuel pump rated at 120 psi I t was controlled by a pwm at 12 volts and work fine at low pressure. But as I increased pressure the internal pressure limiting valve kicked in making for a "pulsating" high-low -high-low flow...

[CMDR_Boom]

I've got some pictures around here somewhere from the year I did my "8 inch" engine nozzle spray test some years ago. I ended up going refurbished pressure washer pump to get enough oomph out of the nozzle I picked up in an salvaged engine basket case of parts awhile before that (I would guess the nozzle is out of a J60-79 era engine). Wow, talk about volume! I would rate it somewhere between commercial fire sprinkler and pumper truck fire hose on flow rate with both primary and secondary lines cued at the same time, and a Huge spray pattern. Granted that was probably with an extra thousand PSI over design spec, but it did the job.